KR20210118052A - Solar cell stacking - Google Patents

Abstract

The present invention relates to a solar cell sheet comprising first and second substrates, the first and second substrates being flexible and suitable for roll-to-roll printing, the solar cell sheet comprising one or more self-contained solar panels also comprising a cell unit, each self-contained photovoltaic cell unit comprising one or more photovoltaic cell modules, each photovoltaic cell module comprising a plurality of series connected photovoltaic cells, wherein each photovoltaic cell The module includes: a first substrate portion of the first flexible substrate and a second substrate portion of the second substrate, a plurality of first electrodes and a plurality of second electrodes disposed between the first and second substrate portions; and at least one organic active layer disposed between the plurality of first electrodes and the plurality of second electrodes, wherein a continuous or discontinuous portion of the first adhesive material surrounds each of the solar cell units. The present invention also relates to a method of making a solar cell sheet comprising one or more self-contained solar cell units.

Description

Solar cell stacking

The present invention relates to a laminated photovoltaic cell sheet and a method for manufacturing a laminated photovoltaic cell sheet.

To mitigate global warming, energy generation must shift from being dominated by fossil fuels to sources with less climate impact. Photovoltaic cells, which directly convert light energy into electrical energy, are expected to become the main source of electricity for future energy systems. Solar cells are typically produced from silicon oxide that is melted, refined, and grown into silicon crystals. This is an energy consuming process, which is why many thin film technologies with low energy consuming manufacturing processes have been developed. In general, thin film solar cells include a photoactive semiconductor sandwiched between two electrodes. An organic solar cell is an example of a thin film solar cell with a photoactive layer composed of a fine mixture of two or more organic semiconductors. A great advantage of this kind of photovoltaic cell is that it can be printed in a roll-to-roll process, thus producing large area photovoltaic cells or photovoltaic modules. In addition, the material use and process energy are very low, so the impact on the climate is very small. These materials are also efficient at converting diffused light into electricity. This allows organic photovoltaic cells to be placed even on vertical surfaces such as walls.

However, the problem of aging and deterioration of materials in photovoltaic modules is a known issue and affects the functioning of the photovoltaic cells over time, leading to reduced efficiency, short circuits and, in the worst case, malfunctioning of the photovoltaic cells. Therefore, there is a need, in particular, to improve the functioning of the solar cell unit over time.

Accordingly, it is an object of the present invention to improve the current state of the art and alleviate at least some of the disadvantages mentioned above. These and other objects are achieved by providing a reinforced solar cell sheet as defined in the appended claims and a method of making such a reinforced solar cell sheet.

Exemplary terms herein are to be understood as examples, instances or examples.

According to a first aspect of the present invention, there is provided a solar cell sheet comprising first and second substrates, wherein the first and second substrates are flexible and suitable for roll-to-roll printing, wherein the solar cell sheet is one Also comprising the above self-contained photovoltaic cell unit, each self-contained photovoltaic cell unit comprising a plurality of series connected photovoltaic cells, each photovoltaic cell module comprising:

a first substrate portion of the first flexible substrate and a second substrate portion of the second substrate;

a plurality of first electrodes and a plurality of second electrodes disposed between the first and second substrate portions;

at least one organic active layer disposed between the plurality of first electrodes and the plurality of second electrodes;

A continuous or discontinuous portion of the adhesive material surrounds and/or defines each solar cell unit.

According to a second aspect of the present invention, there is provided a method of manufacturing a solar cell sheet, the solar cell sheet comprising one or more self-contained solar cell units, each self-contained solar cell unit comprising at least one solar cell unit A photovoltaic module comprising:

- providing first and second flexible substrate portions suitable for roll to roll deposition;

- for each solar cell module, providing a first set of electrodes on a predetermined portion of a first substrate, providing a second set of electrodes on a predetermined portion of a second substrate, a first and providing a first organic active layer on one of the second sets of electrodes, optionally providing a second organic active layer on the other of the first and second sets of electrodes;

- providing a first layer of adhesive material on the first and/or second substrate, the layer of adhesive material being continuous or discontinuous and surrounding and/or defining each of the one or more solar cell units; and/or providing a first layer of adhesive material on the second substrate;

- for each solar cell module, an active layer is spatially disposed between the plurality of first electrodes and the plurality of second electrodes and is in electrical contact with the plurality of first electrodes and the plurality of second electrodes, and laminating the first and second substrate portions together in a roll-to-roll process using heat and pressure such that the first layer adheres the first and second substrates to each other.

The operations listed in the second aspect may include, for example, the first or second deposition of adhesive material on the first and/or second substrate prior to providing the first or alternatively second electrode set on a predetermined portion of the first or second substrate. It is emphasized that the steps of providing the first layer can be performed in any logical order.

The effects and features of these first and second aspects of the present invention are generally similar. Most of the embodiments mentioned below are compatible with both of these aspects of the present invention.

The orientation and extension of the solar cell module is described below and in detail in another patent application EP 3 364 474 A1 of the same applicant using a coordinate system. In essence, the y-direction is orthogonal or perpendicular to the first and second substrates. The z-direction is parallel to the longest extension of the electrode. The x-direction is orthogonal to both the y-direction and the z-direction. The x-direction may be parallel to the longest extension of the substrate portion, but may also be a direction transverse to the longest extension of the substrate portion. The longest direction of the substrate portion may be parallel to the coating direction of the roll-to-roll deposition. The longest direction of the substrate portion may be parallel to the direction of movement of the substrate during roll-to-roll deposition.

a first plurality of gaps typically separate individual electrodes within the first plurality of electrodes from one another; A second plurality of gaps typically separates individual electrodes in the second plurality of electrodes from one another. Specifically, the plurality of first gaps may separate the electrodes in the x-direction.

It should be understood that each electrode of the first and second plurality of electrodes has first and second end portions disposed along the longest extension of the electrode.

According to one example, the solar cell module has the same configuration as described in EP 3 364 474 of the same applicant and incorporated herein by reference, although many other configurations are possible as will be explained in more detail below. According to one general example, a solar cell module comprises a first set of electrode stripes disposed on a first substrate and a set of second electrode stripes disposed on a second substrate, each set of stripes being spaced apart from each other. have. In the final module, the electrodes are sandwiched between the substrates, the active layer is sandwiched between the first and second electrode sets of the electrodes, and the solar cell module in use includes both positive and negative electrodes.

Detailed examples and descriptions of the geometries, extensions of components, suitable materials, processing, fabrication, lamination and placement of photovoltaic cells and photovoltaic modules in the first and second aspects of the invention are found in EP 3 364 474 A1 is provided on Accordingly, these details of solar cell and solar cell module processing have been omitted from the remainder of this description for the sake of brevity.

According to one example, the solar cell sheet is designed to improve the lifespan of large-area thin-film solar cell modules and further increase the mechanical stability and durability of thin-film printed large-area solar cell sheets produced by a roll-to-roll process. are placed

Although adding separation between the substrates increases the likelihood of lack of contact between the layers, we have found that providing an adhesive material to the substrates underneath and/or on top of the solar cell sheet is generally particularly effective over time for solar cell units. found that the functionality of

It should be understood that a solar cell unit means an area on a sheet of solar cells arranged to operate as a self-contained system; Moreover, it is confined and/or surrounded by an adhesive material and comprises at least one solar cell module. The solar cell unit may have a lower portion disposed on the lower substrate of the solar cell sheet and an upper portion disposed on the upper substrate. A plurality of solar cell modules may be disposed in the lower and/or upper portion of the solar cell unit. The solar cell unit is formed by lamination or bonding of the lower and upper substrates. It should also be understood that a solar cell unit may be separated from the remainder of another solar cell unit or sheet, such as through cutting.

For example, the adhesive material surrounding or defining the solar cell unit is preferably wide enough so that the operation of separating or cutting the solar cell unit can be performed without destroying the adhesive properties of the working adhesive material.

The thinner the adhesive, the smaller the passage to the solar cell unit. The wider the adhesive, the better the adhesive properties. Moreover, a separation may be provided between two adjacent lines of adhesive material that further facilitates cutting between the lines of adhesive. The advantage of cutting close to the adhesive is that it reduces the footprint of the unit, reducing its environmental impact. The advantage of cutting further away from the adhesive is that the mechanical stability of the laminate is increased.

It should also be understood that the size, thickness, area, or shape of the solar cell unit may vary as appropriate. For example, the solar cell unit may have any geometric shape such as rectangular, triangular, circular, etc. or may be arranged in any other arbitrary or distorted layout.

Accordingly, the present inventors have found it advantageous to provide a suitably thin layer of adhesive on the underside and/or upper substrate of the solar cell sheet to create a bond between the substrates while achieving adequate contact between the top and bottom electrodes or contacts. found out that

As a non-limiting example, the first and/or second adhesive layer may be deposited as an adhesive solvent or by transfer printing.

According to one example, the thickness of the first and/or second adhesive layer exceeds the surface roughness of the substrate, or is at least 10 nm, or at least 100 nm, or at least 1 μm, or at least 10 μm, or at least 100 μm, or It has at least the same thickness as the stack of layers applied. Additionally or alternatively, the thickness of the first and/or second adhesive layer is at most 5 times or at most 3 times or at most 2 times the thickness of the stack of layers applied to the substrate, or at most 1 mm or at most 100 μm or at most 10 μm. . The above measurements represent the thickness of the adhesive layer after application but before laminating the two substrates.

According to at least one exemplary embodiment of the present invention, the thickness of the substrate portion and/or the second substrate portion is at least 10 μm or at least 50 μm or at least 100 μm; Additionally or alternatively, the thickness of the substrate portion and/or the second substrate portion is at most 50 μm or at most 100 μm or at most 200 μm.

According to an exemplary embodiment of the present invention, the width of the adhesive material after the laminating or gluing step may be at least 10 μm or at least 100 μm or at least 1 mm and/or at most 5 mm or at most 1 mm or at most 0.1 μm.

A thicker layer can create separation between the bottom and top electrodes or contacts, which can lead to breakdown of electrical circuits partially or throughout the solar cell sheet.

According to an exemplary embodiment of the present invention, the thickness of the adhesive material after the laminating or gluing step may be at least 10 nm or 50 nm or 100 nm or 0.5 μm or 1 μm or 10 μm or 100 μm or 1 mm. Optionally or alternatively, the thickness of the adhesive material after the lamination or gluing step may be at most 50 nm or at most 100 nm or at most 0.5 μm or at most 1 μm or 10 μm or at most 100 μm or at most 1 mm. According to one embodiment, these measurements represent the thickness of the adhesive layer after lamination and after drying of the adhesive. According to one example, the thickness of the first adhesive material is determined after the lamination and after evaporation of the solvent from the adhesive.

Drying of the adhesive is to be understood as an adhesive composition in which the solvent evaporates. Thus, drying increases the amount of dry matter in the adhesive.

"After evaporation of the solvent from the adhesive" should be understood as the time when the drying process is completed, that is, when the temperature of the solar cell sheet after the heat-drying step is between 15-40° C. or at least when the production of the solar cell sheet is completed. do. In general, there is an initial faster decrease in solvent, leading to a more stable state. The thickness of the adhesive layer after evaporation of the solvent is preferably determined in said more stable state.

Drying can be accomplished in a separate step involving heating of the solar cell sheet. It can be dried even after lamination at room temperature.

For example, it should be understood that what is said herein with respect to a first adhesive material with respect to thickness and application procedure also applies to a second adhesive material.

According to another exemplary embodiment of the present invention, after the lamination or gluing step, the adhesive material may undergo a change in thickness depending on the compressibility of the adhesive. Other factors that can affect the dimensions of the adhesive in a laminated article are, for example, vapor pressure and wetting of the adhesive to the substrate and its associated effects.

It should be noted that the thickness of the plurality of first electrodes and the plurality of second electrodes may be at least 20 nm or 50 nm, and/or at most 300 nm or 2000 nm. Furthermore, the combined thickness of the active layer may be at least 30 nm or 80 nm and/or at most 350 nm or 1000 nm.

A thicker adhesive layer provides better adhesion and a thinner adhesive layer prevents overflow of adhesive material when performing lamination or gluing of solar cell sheet substrates. In addition, a larger working area and unobstructed electrical contact provides a sufficiently thin adhesive layer.

According to one exemplary embodiment of the present invention, the adhesive material prior to the laminating or gluing step may have a width of at least 0.5 mm and/or at most 1 mm or at most 5 mm. The adhesive layer may undergo changes in width and thickness during the bonding or lamination step.

According to one embodiment, the first and/or second adhesive material is partially or completely composed of a hydrophobic adhesive material. This has the advantage of protecting the inner part of the photovoltaic unit from external moisture or maintaining the inner part of the photovoltaic unit at slightly higher or lower humidity compared to the ambient humidity. This adjusted operating humidity of the interior portion of the solar cell unit can be advantageous in making solar cell sheets for use in different climatic conditions and thermal cycles.

According to one embodiment, the first and/or second adhesive material is partially or completely composed of an adhesive material having low oxygen permeability.

Additionally, the adhesive material may function as a separating layer between the inner portion of the solar cell unit and the outer portion of the solar cell unit that may be immediately exposed to the external environment. Thus, the adhesive material may protect the solar cell unit from penetration of unwanted moisture, oxygen, dust particles or any type of aerosol particles that may interfere with the functioning of the solar cell unit.

According to one example, the first and/or second adhesive comprises a first line or stripe surrounding and/or defining the solar cell unit. In addition to this first line/stripe, the adhesive also comprises a second line or stripe surrounding and/or defining the solar cell unit, the second line/stripe preferably proximate to said first line/stripe. are placed According to one embodiment, each of the lines/stripes only partially surrounds the solar cell unit, and together they completely surround the solar cell unit. According to another embodiment, one or both of the lines completely surround the solar cell unit. The first and second lines/stripes may be the same or different adhesive materials. One of the lines/stripe may be constructed of, for example, a hydrophobic adhesive material designed to reduce the passage of moisture; Another line may be constructed of, for example, an adhesive material with low oxygen permeability designed to reduce the passage of oxygen. The lines may also include interleaved or alternating portions of hydrophobic adhesive material and adhesive material having low oxygen permeability along the extension of the line.

According to another embodiment of the present invention, the first adhesive material may be conductive or non-conductive. This has the advantage of an adhesive material that acts as an insulator in a specific direction to prevent short circuits from occurring.

According to an exemplary embodiment of the present invention, the solar cell sheet may further be provided with a plurality of discrete portions of non-conductive adhesive material spatially disposed within each solar cell module.

The solar cell includes a first set of electrodes disposed on a first substrate and a second set of electrodes disposed on a second substrate. the outermost edge portion of the outermost electrode defines an outer edge portion of the inner region of the solar cell module in a direction substantially along the extension of the electrode; The extension of the electrode in the y-direction defines an outer edge of the inner region in a direction substantially transverse to the extension of the electrode.

That is, in terms within a solar cell module, for example, on the first and/or second substrate or within the inner region and between the first and second substrates, it should be understood as the space inside the inner region of the solar cell module.

The lifetime and mechanical durability of the solar cell sheet by further providing each and/or multiple solar cell modules an additional discontinuous portion of a second, non-conductive adhesive material spatially disposed within each solar cell module. this further increases This is of particular interest in creating large areas of flexible solar cell sheets where mechanical deformation or ambient temperature and humidity conditions can cause the top and bottom substrates of the solar cell sheet to break more often.

In another exemplary embodiment of the present invention, the adhesive material can be colored in any color such as, for example, black, red, white or green, so that it can be decorated or easily observed on a first or second substrate having an aesthetic appearance. You can create boundaries where you can.

ingredient

The plurality of first and second electrodes includes an electrode material, which may be a conductive organic compound, a metal, a metal oxide, or a combination thereof. The conductive organic compound may be, for example, a small conductive organic molecule or a conductive polymer. The conductive polymer may be, for example, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) or a variant thereof, for example PEDOT:PSS PH1000. The metal may be selected from a list including, but not limited to, aluminum (Al), chromium (Cr), titanium (Ti), copper (Cu), gold (Au), and silver (Ag). The metal oxide may be, for example, indium tin oxide (ITO) and aluminum zinc oxide (AZO). According to at least one exemplary embodiment of the present invention, the electrode may comprise one or more layers. For example, the electrode may be an ITO/metal/ITO (IMI) electrode comprising a first layer of ITO, a second layer of metal and a third layer of ITO. The electrode may comprise, for example, ITO/Ag/ITO.

It should be understood that the plurality of first and second electrodes may extend in any direction over the substrate portion and may have any extension, eg, straight or curved. The plurality of first and second electrodes may also be parallel or non-parallel. Moreover, it should be understood that the plurality of first and second electrodes may have substantially the same width over their entire length or may have varying widths over their entire length. The plurality of first and second electrodes may all have the same width or different electrodes may have different widths.

The plurality of first and second electrodes may be provided by a variety of deposition techniques, for example, by thermal evaporation, sputtering, spray-coating, printing or coating such as slot-die coating. According to at least one embodiment of the present invention, the plurality of first electrodes and the plurality of second electrodes may be provided by the same deposition technique. According to at least another exemplary embodiment of the present invention, the plurality of first and second electrodes may be provided by different techniques.

The first and second contact electrodes may comprise, for example, a first layer of electrode material provided by evaporation, spray-coating or printing and a busbar connected thereto. The bus bar can be made of, for example, graphite or silver, and can be screen printed. Optionally, instead of or in addition to the bus bar, the connecting electrode may comprise an additional printed or laminated layer. The contact electrode can be divided into two parts, the first part can be used as one of the electrodes in one photovoltaic cell included in the photovoltaic cell module, the other part is the photovoltaic cell module when the photovoltaic cell module is in use is used to connect to a unit for collecting electricity. Some of the contact electrodes used to connect solar cell modules are usually not covered with an active layer.

adhesive material

The first and/or second adhesive material may be a thermoplastic polymer such as a thermoplastic polyurethane, polypropylene, polybutylene, polyvinyl butyral, ethyl vinyl acetate, polystyrene butadiene copolymer or ethylene vinyl alcohol copolymer and their Combinations may be included.

Additionally or alternatively, the first and/or second adhesive material may comprise a UV curable polymer, such as an acrylic and/or epoxy based UV curable polymer.

contact electrode material

The contact electrode includes an electrode material that may include a conductive organic compound, a conductive carbon compound, a metal, a metal oxide, or a combination thereof. The conductive organic compound may be, for example, a small conductive organic molecule or a conductive polymer. The conductive polymer may be, for example, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) or a variant thereof, for example PEDOT:PSS PH1000. The conductive carbon compound may be provided as a carbon paste or graphite or graphene. The metal may be selected from a list including, but not limited to, aluminum (Al), chromium (Cr), titanium (Ti), copper (Cu), gold (Au), and silver (Ag). The metal oxide may be selected from a list including, but not limited to, indium tin oxide (ITO) and aluminum zinc oxide (AZO). According to at least one exemplary embodiment of the present invention, the metal is provided as an ink in which the metal is provided as nanoparticles, such as, for example, nano-spheres or nano-rods. According to at least one exemplary embodiment of the present invention, the electrode may comprise one or more layers. For example, the electrode may be an ITO/metal/ITO (IMI) electrode comprising a first layer of ITO, a second layer of metal and a third layer of ITO. The electrode may comprise, for example, ITO/Ag/ITO. The electrode material may be the same electrode material for the plurality of first or second electrodes or may be different electrode materials.

active layer material

The continuous or discontinuous active layer or the first and second continuous or discontinuous active layers may comprise a compound that absorbs a wavelength within the range of 350-950 nm, for example, light within the visual spectrum, i.e., a wavelength within the range of 400 nm to 700 nm. can absorb. Moreover, the compound must be able to provide an electric charge due to absorption of light.

The continuous active layer is an active layer covering both the plurality of gaps between the electrodes and the plurality of first or second electrodes in both the x-direction and the z-direction, so that the photoactive region, that is, the region where the light of the solar cell module is absorbed. It should be understood that this increases. Moreover, it should be understood that the first continuous active layer covers both the first plurality of electrodes and the plurality of gaps therebetween. In the same manner, the second continuous active layer covers both the plurality of second electrodes and the plurality of gaps therebetween. That is, it should be understood that the continuous active layer or the first and second continuous active layers are provided entirely over the plurality of first and second electrodes and the gaps between each of the plurality of first and second electrodes. According to at least one exemplary embodiment, the continuous active layer or the first and/or second continuous active layer may be an organic active layer and may include a donor material and/or an acceptor material. According to at least one exemplary embodiment, all active layers of the solar cell sheet are organic active layers. The donor material may be a semi-conducting polymer or a semi-conducting small organic molecule. Semi-conducting polymers are, for example, polythiophene, polyaniline, polypyrrole, polycarbazole, polyvinylcarbazole, polyphenylene, polyphenylvinylene, polysilane, polythienylenevinylene, polyisothianaphtanene, Polycyclopentadithiophene, polysilacyclopentadithiophene, polycyclopentadithiazole, polythiazolothiazole, polythiazole, polybenzothiadiazole, poly(thiophene oxide), poly(cyclopentadithiophenoxide) , polythiadiazoloquinoxaline, polybenzoisothiazole, polybenzothiazole, polythienothiophene, poly(thienothiophene oxide), polydithienothiophene, poly(dithienothiophene oxide), polytetrahydro any semi-conducting polymer and derivatives thereof, including but not limited to isoindole and copolymers thereof. The semiconducting polymer may also be an iso-indigo-based polymer. Specifically, the semi-conductor polymer may be, for example, P3HT, PTB7, TQ1, P3TI, PCDTBT or PffBT4T-20D. A semi-conducting small molecule may be, for example, a molecule comprising at least one benzodithiophene group, such as DRTB-T or BDT3TR. The acceptor material may be, for example, a semi-conducting polymer or a semi-conducting small molecule. The semi-conducting polymer may be, for example, N2200 or PNDI-T10. Semi-conducting small organic molecules can be, for example, fullerenes, fullerene derivatives or (5Z,5'Z)-5,5'-{(9,9-dioctyl-9H-fluorene-2,7-diyl)bis [2,1,3-benzothiadiazole-7,4-diyl(Z)methylylidene]}bis(3-ethyl-2-thioxo-1,3-thiazolidin-4-one) (FBR ) or 3,9-bis(2-methylene-(3-(1,1-dicynomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno Any other semi-conducting small molecule, such as [2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene) (ITIC) can be The fullerene derivative may be phenyl-C61-butyric acid methyl ester (PC61BM), phenyl-C71-butyric acid methyl ester (PC71BM), indene-C60-double adduct (ICBA), O-IDTBR or IC-C6IDT-IC.

According to at least one exemplary embodiment of the present invention, the mixture of donor and acceptor material may be provided as a bulk-heterojunction.

In addition, electrodes, contact electrodes, active layers may be provided with more materials and additional deposition techniques than those mentioned above, details of which can be found in document EP 3 364 474 A1, which is hereby incorporated by reference. .

According to another exemplary embodiment of the present invention, each of the at least one solar cell module is surrounded/delimited by a continuous or discontinuous portion of the first adhesive material.

According to another exemplary embodiment of the present invention, the first adhesive layer may be discontinuous, and along one direction of the extension of the second adhesive layer and within the solar cell module the ratio between covered and uncovered areas may be at least 1% or at least 10% or at least 20% and/or at most 40% or at most 30% or at most 25%.

According to another exemplary embodiment of the present invention, the second adhesive material may be optically transparent within the wavelength range of the at least one organic active layer.

According to another exemplary embodiment of the present invention, a method of manufacturing a solar cell sheet comprises a plurality of discontinuous portions of a second non-conductive adhesive material spatially disposed within a solar cell module in each of at least one solar cell module. It may also include the step of providing

According to another exemplary embodiment of the present invention, a method for manufacturing a solar cell sheet comprises, for each solar cell module, a plurality of discontinuous portions of the second non-conductive adhesive material to connect two opposing portions of the solar cell module. It may also include laminating the first and second substrate portions together in a roll-to-roll process using heat and pressure to bond them together.

According to another exemplary embodiment of the present invention, the first and second adhesive materials may be UV-adhesive/UV-curable adhesive materials.

These and other features of the present invention will become more apparent in the following with reference to embodiments described hereinafter.

Additional objects, features and advantages of the present invention, as well as said objects, will be more fully understood by reference to the following illustrative and non-limiting detailed description of embodiments of the present invention when taken in conjunction with the accompanying drawings.

1A is a schematic cross-sectional plan view of a solar cell sheet having a solar cell unit in accordance with at least one embodiment of the present invention.
1B-1D are schematic top cross-sectional views of one of the solar cell units of FIG. 1A in accordance with at least one embodiment of the present invention.
2 is a schematic top cross-sectional view of upper and lower portions of the solar cell unit of FIG. 1A in accordance with at least one embodiment of the present invention;
3A-3D are schematic top cross-sectional views of a plurality of solar cell units in accordance with at least one embodiment of the present invention.
4 is a schematic top cross-sectional view of various adhesive material layouts in accordance with at least one embodiment of the present invention.
5A-5D are schematic top and side cross-sections of a plurality of solar cells in accordance with at least one embodiment of the present invention.

In this detailed description, embodiments of the present invention will be discussed in conjunction with the accompanying drawings. This in no way limits the scope of the present invention, for example, in other environments with other types or variations of the method of stacking solar cell modules or modifications of solar cell modules other than the embodiments shown in the accompanying drawings. It should be noted that this is applicable. Further, reference to a particular feature in connection with an embodiment of the present invention does not mean that such component cannot be advantageously used in conjunction with other embodiments of the present invention.

The following description uses terms such as "upper", "lower", "outer" and the like. These terms generally refer to the views and orientations indicated in the drawings. This term is used only for the convenience of the reader and is not limiting.

1A schematically shows a solar cell module 6 comprising a first set of electrode stripes 52 disposed on a first substrate and a second set of electrode stripes disposed on a second substrate, each set of The stripes are separated from each other by a gap 54 . Moreover, the electrode is sandwiched between the first and second substrates, and the active layer is sandwiched between the first and second electrode sets. Additionally, the solar cell module includes first and second electrodes or bus bars 57a, 57b for extracting the generated energy.

1B shows one example of a solar cell module surrounded and bounded by an adhesive material 5 , which may be a conductive adhesive or a non-conductive adhesive material that surrounds/defines an area of the solar cell unit 4 . The adhesive material 5 divides the substrate into an inner portion 4a and an outer portion 4b. The inner part 4a comprises at least one solar cell module 6 as shown in FIG. 1b .

5B to 5D , the solar cell module 6 comprises a first flexible substrate portion 10 having disposed thereon a plurality of first electrodes 52 and a first continuous or discontinuous active layer 53 . . The first substrate portion 10 may be transparent or semi-transparent. The first substrate portion 10 and the first plurality of electrodes 52 are formed by roll-to-roll processing methods such as, for example, roll-to-roll printing, roll-to-roll coating, and roll-to-roll lamination. suitable for

The plurality of first electrodes 52 are provided as substantially parallel stripes on the first substrate portion 10 . The plurality of first electrodes 52 extend along the substrate in the z-direction. That is, the stripe longest extension is here in the z-direction. As shown in FIG. 5A , the longest extensions of the first substrate portion 10 and the plurality of first electrodes 52 are in the same direction here. The plurality of first electrodes 52 are arranged to be spatially separated from each other in the x-direction, and this separation forms a plurality of gaps 54 between the first electrodes 52 . In alternative embodiments, the longest extension of the stripe may be in a direction transverse or orthogonal to the longest extension of the substrate. Specifically, when the longest extension portion of the substrate is in the z direction, the longest direction of the plurality of first electrodes 52 may be the x direction or any direction between x and z.

The solar cell module 6 may also include a second flexible substrate portion 20 having the same configuration as described with respect to the first substrate, unless otherwise stated. That is, there may be a plurality of second electrodes 522 and a second continuous or discontinuous active layer 53 .

The solar cell module 6 may also include first and second contact electrodes 56a, 56b optionally comprising respective first and second bus bars 57a, 57b or contacts.

The thicknesses of the different layers, eg, the first and second active layers 53 , or the plurality of first or second electrodes 52 or 52 , are not drawn to scale.

Alternatively, the solar cell module 6 can be arranged as described in EP 3 364 474 A1.

In another example shown in FIG. 1C , the solar cell unit 4 may include one or more solar cell modules 6 .

According to another example shown in FIGS. 1D and 1E , the solar cell unit also includes other types of components 102 , such as logic circuits or planar PCBs. The component is optionally attached to the contact 101 , connected to the solar cell by means of an electronic conductor 100a , and may include an additional electrode 100b for connection to other devices. In Fig. 1d the photovoltaic cell unit is in a state with no adhesive applied thereon, and in Fig. 1e the photovoltaic cell unit is shown before being laminated to the second substrate when the adhesive is applied (preferably at least covering the electronic conductors). portion is non-conductive).

2 shows one example of forming a photovoltaic cell unit 4 on a photovoltaic cell sheet 1 , wherein the photovoltaic cell module 6 is disposed on a lower substrate 2 , and an upper substrate ( 3) is provided with an adhesive material 5 .

In the arrangement of the above example, the adhesive material 5 is applied on the lower substrate 2 as stripes 7 having intersecting continuous portions 8 extending continuously in the z direction and further extending in the x direction. More specifically, the intersection where the extensions of adhesive material extending in the x and z directions meet create a defined interior area 4a of the solar cell unit with a ladder-like appearance. By laminating the upper and lower substrates 2 and 3 together while aligning the adhesive portion 5 to each substrate, a finished solar cell sheet is produced.

According to one embodiment, the adhesive material is placed close to the top of the solar cell module (within 10 nm to 1 mm from the solar cell) or even as the minimization of the gap at the inner surface enables a reduction of air pockets in the finished product. It is printed on the top of the solar cell module.

According to another embodiment, each solar cell unit 4 may be individually defined by an adhesive material as shown in FIG. 3A . In this embodiment, each solar cell unit 4 is defined by an adhesive boundary line surrounding each solar cell unit, the boundary line being a gap 31 between two adjacent solar cell units 4 . and can facilitate the separation of the solar cell unit 4 while maintaining the adhesive properties of the adhesive. Additionally, it is possible to reduce the amount of adhesive material required for bonding the solar cell substrate 1 . Also, as shown in FIGS. 3B and 3C , the photovoltaic cell sheet 1 comprises, for example, a single photovoltaic cell unit 33 that extends completely or substantially over the entire area of the photovoltaic cell sheet 1 . may include A single photovoltaic cell unit 33 may include a plurality of photovoltaic cell modules 6 as shown in FIG. 3b or a single photovoltaic cell module extending across the entire unit as shown in FIG. 3c ( 6) may be included. The photovoltaic cell modules 6 in each photovoltaic cell unit 4 , 33 are individually connected to contact electrodes or bus bar contacts, or electrically in series or parallel to form an extended network of photovoltaic cell modules. can be connected

To produce the solar cell sheet 1 , the adhesive layer may be applied to both the lower substrate 2 and the upper substrate 3 or only one of the substrates. The adhesive material 5 may be provided in any geometric shape or contour, with circular, triangular or rectangular shapes being basic examples. As shown in FIG. 4 , the adhesive material 5 may be applied in a continuous manner, for example in a continuous line 41 , a dashed line 42 or any other layout 43 required for the manufacturing process. The adhesive layer may be applied on the substrate as separate parts 43 disposed with a separation gap determined relative to each other as shown in FIG. 4 . However, after the step of gluing or laminating the lower substrate 2 and the upper substrate 3 , the adhesive material 5 applied in any of the above-mentioned manners is a continuous boundary 44 defining the solar cell unit 4 . It is advantageous to form The defined boundary 44 serves as a barrier between the inner portion 4a and the outer portion 4b of the solar cell module 4 and may function to maintain isolation between the solar cell unit and the external environment. . For example, humidity conditions inside the unit may be configured to maintain a constant level with respect to ambient humidity. It also protects the unit from external pollutants such as dust particles or atmospheric particulate matter such as smog, soot, etc. that enters and destroys the solar cell module 6 . That is, the adhesive layer not only improves the mechanical stability of the solar cell sheet 1 but also functions as a protective barrier that protects the solar cell unit 4 from the external environment.

According to one example, the boundary 44 comprises a first line surrounding and/or delimiting the solar cell unit. In addition to this first line, the boundary also comprises a second line surrounding and/or delimiting the solar cell unit, the second line being preferably arranged close to said first line. According to one embodiment, each of the lines only partially surrounds the solar cell unit, and together they completely surround the solar cell unit. According to another embodiment, one or both of the lines completely surround the solar cell unit. The first and second lines may be the same or different adhesive materials. One of the lines may be constructed of, for example, a hydrophobic adhesive material designed to reduce the passage of moisture; Another line may be constructed of, for example, an adhesive material with low oxygen permeability designed to reduce the passage of oxygen. The lines may also include interleaved or alternating portions of hydrophobic adhesive material and adhesive material having low oxygen permeability along the extension of the line.

permeable design; That is, moisture permeability through the hydrophobic adhesive material is a line. This second line partially or completely surrounds the solar cell unit, while the first line completely surrounds the solar cell unit.

In another exemplary embodiment, as shown in the top cross-sectional view of the solar cell module in FIG. 5A , the solar cell module 6 may include a separate portion 51 of adhesive material disposed within each solar cell module. can These portions may be arranged in various spatial distributions on the substrate portions 10 , 20 . For example, FIG. 5B shows a cross-sectional side view of the same solar cell module 6 of FIG. 5A with five solar cells in the lower substrate portion. In this embodiment, a portion 51 of adhesive material is disposed within a gap 54 created between adjacent electrodes 52 , 522 . In this example, the discontinuous adhesive material is a non-conductive material. As mentioned above, the solar cell module 6 may optionally include or not include a continuous or discontinuous active layer 53 on the second substrate portion. In this example, the active layer 53 is provided only on the first substrate portion 10 .

5C and 5D , the active layer 53 may be discontinuous, and the first and second electrodes are in the gaps of adjacent electrodes on the first and second substrate portions 10 , 20 . may be connected via an electrical conductor 55 disposed within 54 . In this case, the adhesive material may be disposed on the first active layer 531 and/or the second active layer (not shown) of the first substrate portion 10 and the second substrate portion 20 . Optionally, the adhesive material is transparent within the operating wavelength of the solar cell so as not to affect the functionality of the module.

In another example shown in FIG. 5D , in the same solar cell module 6 of FIG. 5C , the discontinuous portion 51 of adhesive material comprises a gap 54 between the contact electrodes 56a and 66b, a first active layer and It may be disposed within the gap 54 between the bus bar contacts 57a and 57b or the gap 54 between the contact electrodes 56a and 66b and the bus bar contacts 57a and 57b.

Those skilled in the art will recognize that many modifications of the embodiments described herein are possible without departing from the scope of the invention as defined in the appended claims. For example, a plurality of stripes of adhesive material used may be applied on the substrate in any other location, as well as geometric shapes and arrangements, than those described in the examples above. Also, other components of the solar cell unit, such as the first and second electrodes, may have any curvature other than those shown in the figures, for example. They may also be deposited such that their longest extension is in any direction between the x-direction and the z-direction. They need not be parallel or perpendicular to the longest extension of the substrate. Those skilled in the art will also recognize that other conductive or semiconducting materials may be used as the active layer of the electrode or solar cell module.

Claims (15)

A solar cell sheet comprising a first and a second substrate,
The first and second substrates are flexible and suitable for roll to roll printing, the solar cell sheet also comprising one or more self-contained solar cell units, each self-contained solar cell unit comprising one or more solar cells A cell module comprising: each photovoltaic cell module comprising a plurality of series-connected photovoltaic cells;
Each of the solar cell modules,
a first substrate portion of the first flexible substrate and a second substrate portion of the second substrate;
a plurality of first electrodes and a plurality of second electrodes disposed between the first and second substrate portions;
at least one organic active layer disposed between the plurality of first electrodes and the plurality of second electrodes;
A continuous or discontinuous portion of a first adhesive material surrounds each of the solar cell units, and the thickness of the first adhesive material is at most 10 μm. According to claim 1,
and a plurality of discrete portions of a second non-conductive adhesive material are spatially disposed within said respective solar cell module. According to any one of the preceding claims,
the first adhesive material is conductive or non-conductive, and/or the first adhesive material at least partially comprises an outer and an inner line, optionally one of the outer and inner lines is hydrophobic relative to the other line, Optionally, the other of the outer and inner lines is a solar cell sheet, characterized in that it has a higher oxygen permeability than the other lines. 4. The method of claim 2 or 3,
The photovoltaic cell sheet, characterized in that the first and/or the second adhesive material is a hydrophobic adhesive material. According to any one of the preceding claims,
wherein the thickness of the first adhesive material is at least 10 nm. According to any one of the preceding claims,
A photovoltaic cell sheet, characterized in that the width of the first adhesive material is at least 10 μm and/or at most 0.1 mm. According to any one of the preceding claims,
wherein each of said at least one solar cell module is surrounded/delimited by a continuous or discontinuous portion of said first adhesive material. 8. The method according to any one of claims 2 to 7,
the second adhesive layer is discontinuous and the ratio between covered and uncovered areas within the solar cell module is at least 1% or at least 10% or at least 20% and/or at most 40% or at most 30% or at most 25 %, characterized in that the solar cell sheet. According to any one of the preceding claims,
and the second adhesive material is optically transparent or semi-transparent within the wavelength range of the at least one organic active layer. A method for manufacturing a solar cell sheet, comprising:
The solar cell sheet includes one or more self-contained solar cell units, each self-contained solar cell unit includes one or more solar cell modules, the method comprising:
- providing first and second flexible substrate portions suitable for roll to roll deposition;
- for each solar cell module, providing a first set of electrodes on a predetermined portion of the first substrate, providing a second set of electrodes on a predetermined portion of the second substrate; providing a first organic active layer on one of the first and second sets of electrodes and optionally providing a second organic active layer on the other of the first and second sets of electrodes;
- providing a first layer of adhesive material on said first and/or second substrate, said layer of adhesive material being continuous or discontinuous and surrounding each of said one or more solar cell units; /or providing a first layer of adhesive material on the second substrate;
- a first layer of adhesive material adheres the first and second substrates to each other, and for each solar cell module, an active layer is spatially disposed between said plurality of first electrodes and said plurality of second electrodes; and laminating the first and second substrate portions together in a roll-to-roll process using heat and pressure to make electrical contact with the plurality of first electrodes and the plurality of second electrodes. A method for manufacturing a solar cell sheet. 11. The method of claim 10,
The thickness of the first adhesive material is a solar cell sheet manufacturing method, characterized in that after the lamination up to 10㎛. 12. The method of claim 10 or 11,
The method further comprises providing to each of the at least one solar cell module a plurality of discrete portions of a second non-conductive adhesive material spatially disposed within the solar cell module. How to make a sheet. 13. The method of claim 12,
The method uses heat and pressure to roll-to-roll such that for each solar cell module the plurality of discontinuous portions of a second non-conductive adhesive material adhere two opposing portions of the solar cell module to each other. and laminating the first and second substrate portions together in a roll process. 14. The method according to any one of claims 10 to 13,
A method for manufacturing a solar cell sheet, characterized in that the width of the first and/or second adhesive material after drying is at least 10 nm and/or at most 1 mm. 15. The method according to any one of claims 10 to 14,
wherein the first adhesive layer is applied discontinuously, and the ratio between the covered area and the uncovered area along the longest extension of the first adhesive layer is between 1% and 40%.

Images